For six months, at least once a day, and many times more often, I floated above
the large observation window in the Kvant-2 module of Mir and gazed at the earth
below or into the depths of the universe. Invariably, I was struck by the majesty
of the unfolding scene. But to be honest, the most amazing thing of all was
that here I was, a child of the pre-Sputnik, cold war 1950s, living on a Russian
space station. During my early childhood in the Texas Panhandle, I had spent
a significant amount of time chasing windblown tumbleweeds across the prairie.
Now I was in a vehicle that resembled a cosmic tumbleweed, working and socializing
with a Russian air force officer and a Russian engineer. Just 10 years ago such
a plot line would have been deemed too implausible for anything but a science-fiction
novel.

In the early 1970s both the American and Russian space agencies began exploring
the possibility of long-term habitation in space. After the end of the third
Skylab mission in 1974, the American program focused on short-duration space
shuttle flights. But the Russians continued to expand the time their cosmonauts
spent in orbit, first on the Salyut space stations and later on Mir, which means
"peace" in Russian. By the early 1990s, with the end of the cold war, it seemed
only natural that the U.S. and Russia should cooperate in the next major step
of space exploration, the construction of the International Space Station. The
Russians formally joined the partnership-which also includes the European, Japanese,
Canadian and Brazilian space agencies-in 1993.

The first phase of this partnership was the Shuttle-Mir program. The National
Aeronautics and Space Administration planned a series of shuttle missions to
send American astronauts to the Russian space station. Each astronaut would
stay on Mir for about four months, performing a wide range of peer-reviewed
science experiments. The space shuttle would periodically dock with Mir to exchange
crew members and deliver supplies. In addition to the science, NASA's goals
were to learn how to work with the Russians, to gain experience in long-duration
spaceflight and to reduce the risks involved in building the International Space
Station. Astronaut Norm Thagard was the first American to live on Mir. My own
arrival at the space station-eight months after the end of Thagard's mission-was
the beginning of a continuous American presence in space, which has lasted for
more than two years.

My involvement with the program began in 1994. At that point, I had been a
NASA astronaut for 15 years and had flown on four shuttle missions. Late one
Friday afternoon I received a phone call from my boss, Robert "Hoot" Gibson,
then the head of NASA's astronaut office. He asked if I was interested in starting
full-time Russian-language instruction with the possibility of going to Russia
to train for a Mir mission. My immediate answer was yes. Hoot tempered my enthusiasm
by saying I was only being assigned to study Russian. This did not necessarily
mean I would be going to Russia, much less flying on Mir. But because there
was a possibility that I might fly on Mir and because learning Russian requires
some lead time-a major understatement if ever there was one-Hoot thought it
would be prudent for me to get started.

I hung up the phone and for a few brief moments stared reality in the face.
The mission on which I might fly was less than a year and a half away. In that
time I would have to learn a new language, not only to communicate with my crewmates
in orbit but to train in Russia for the mission. I would have to learn the systems
and operations for Mir and Soyuz, the spacecraft that transports Russian crews
to and from the space station. Because I would be traveling to and from Mir
on the space shuttle, I needed to maintain my familiarity with the American
spacecraft. As if that were not enough, I would also have to master the series
of experiments I would be conducting while in orbit.

It is fair at this point to ask, "Why?" Why would I wish to live and work on
Mir? And from a broader perspective, why are so many countries joining together
to build a new space station? Certainly one reason is scientific research. Gravity
influences all experiments done on the earth except for investigations conducted
in drop towers or on airplanes in parabolic flight. But on a space station,
scientists can conduct long-term investigations in an environment where gravity
is almost nonexistent-the microgravity environment. And the experience gained
by maintaining a continuous human presence in space may help determine what
is needed to support manned flights to other planets.

From a personal standpoint, I viewed the Mir mission as a perfect opportunity
to combine two of my passions: flying airplanes and working in laboratories.
I received my private pilot's license when I was 20 years old and have been
flying ever since. And before I became an astronaut, I was a biochemist, earning
my Ph.D. from the University of Oklahoma in 1973. For a scientist who loves
flying, what could be more exciting than working in a laboratory that hurtles
around the earth at 17,000 miles (27,000 kilometers) per hour?

After three months of intensive language study, I got the go-ahead to start
my training at Star City, the cosmonaut training center outside Moscow. My stay
there began in January 1995, in the depths of a Russian winter. Every morning
I woke at five o'clock to begin studying. As I walked to class I was always
aware that one misstep on the ice might result in a broken leg, ending my dreams
of a flight on Mir. I spent most of my day in classrooms listening to Mir and
Soyuz system lectures-all in Russian, of course. In the evenings I continued
to study the language and struggled with workbooks written in technical Russian.
At midnight I finally fell exhausted into bed.

I worked harder during that year than at any other time in my life. Going
to graduate school while raising toddlers was child's play in comparison. (Fortunately,
my three children were grown by this point, and my husband was able to visit
me in Russia.) At last, in February 1996, after I had passed all the required
medical and technical exams, the Russian spaceflight commission certified me
as a Mir crew member. I traveled to Baikonur, Kazakhstan, to watch the launch
of the Soyuz carrying my crewmates-Commander Yuri Onufriyenko, a Russian air
force officer, and flight engineer Yury Usachev, a Russian civilian-to Mir.
Then I headed back to the U.S. for three weeks of training with the crew of
shuttle mission STS-76. On March 22, 1996, we lifted off from the Kennedy Space
Center on the shuttle Atlantis. Three days later the shuttle docked with Mir,
and I officially joined the space station crew for what was planned to be a
four-and-a-half-month stay.

Living in Microgravity

My first days on Mir were spent getting to know Onufriyenko and Usachev-we
spoke exclusively in Russian-and the layout of the space station. Mir has a
modular design and was built in stages. The first part, the Base Block, was
launched in February 1986. Attached to one end of the Base Block is Kvant-1,
launched in 1987, and at the other end is Mir's transfer node, which serves
the same function as a hallway in a house. Instead of being a long corridor
with doors, though, the transfer node is a ball with six hatches. Kvant-2 (1989),
Kristall (1990) and Spektr (1995) are each docked to a hatch. During my stay
on Mir, the Russians launched Priroda, the final module of the space station,
and attached it to the transfer node. Priroda contained the laboratory where
I conducted most of my experiments. I stored my personal belongings in Spektr
and slept there every night. My commute to work was very short-in a matter of
seconds I could float from one module to the other.

The two cosmonauts slept in cubicles in the Base Block. Most mornings the wake-up
alarm went off at eight o'clock (Mir runs on Moscow time, as does the Russian
mission control in Korolev). In about 20 minutes we were dressed and ready to
start the day. The first thing we usually did was put on our headsets to talk
to mission control. Unlike the space shuttle, which transmits messages via a
pair of communications satellites, Mir is not in constant contact with the ground.
The cosmonauts can talk to mission control only when the space station passes
over one of the communications ground sites in Russia. These "comm passes" occurred
once an orbit-about every 90 minutes-and generally lasted about 10 minutes.
Commander Onufriyenko wanted each of us to be "on comm" every time it was available,
in case the ground needed to talk to us. This routine worked out well because
it gave us short breaks throughout the day. We gathered in the Base Block and
socialized a bit before and after talking with mission control.

After the first comm pass of the day, we ate breakfast. One of the most pleasant
aspects of being part of the Mir crew was that we ate all our meals together,
floating around a table in the Base Block. Preflight, I had assumed that the
repetitive nature of the menu would dampen my appetite, but to my surprise I
was hungry for every meal. We ate both Russian and American dehydrated food
that we reconstituted with hot water. We experimented with mixing the various
packages to create new tastes, and we each had favorite mixtures that we recommended
to the others. For breakfast I liked to have a bag of Russian soup-usually borscht
or vegetable-and a bag of fruit juice. For lunch or supper I liked the Russian
meat-and-potato casseroles. The Russians loved the packets of American mayonnaise,
which they added to nearly everything they ate.

Our work schedule was detailed in a daily timeline that the Russians called
the Form 24. The cosmonauts typically spent most of their day maintaining Mir's
systems, while I conducted experiments for NASA. We had to exercise every day
to prevent our muscles from atrophying in the weightless environment. Usually,
we all exercised just before lunch. There are two treadmills on Mir-one in the
Base Block and the other in the Kristall module-and a bicycle ergometer is stored
under a floor panel in the Base Block. We followed three exercise protocols
developed by Russian physiologists; we did a different one each day, then repeated
the cycle. Each protocol took about 45 minutes and alternated periods of treadmill
running with exercises that involved pulling against bungee cords to simulate
the gravitational forces we were no longer feeling. Toward the end of my stay
on Mir I felt that I needed to be working harder, so after I finished my exercises
I ran additional kilometers on the treadmill.

I'll be honest: the daily exercise was what I disliked most about living on
Mir. First, it was just downright hard. I had to put on a harness and then connect
it with bungee cords to the treadmill. Working against the bungees allowed me
to stand flat on the device. With a little practice, I learned to run. Second,
it was boring. The treadmill was so noisy you could not carry on a conversation.
To keep my mind occupied, I listened to my Walkman while running, but soon I
realized I'd made a huge preflight mistake. I had packed very few tapes with
a fast beat. Luckily, there was a large collection of music tapes on Mir. During
my six-month stay, I worked through most of them.

When we had finished exercising, we usually enjoyed a long lunch, then returned
to our work. Many times in the late afternoon we had a short tea break, and
in the late evening we shared supper. By this point we had usually finished
all the assignments on the Form 24, but there were still many housekeeping chores
that needed to be done: collecting the trash, organizing the food supply, sponging
up the water that had condensed on cool surfaces. Clutter was a problem on Mir.
After we had unloaded new supplies from the unmanned Progress spacecraft that
docked with the space station once every few months, we could put human wastes
and trash into the empty vehicles, which would burn up on reentry into the atmosphere.
But there was usually no room left on Progress for the many pieces of scientific
equipment that were no longer in use.

After supper, mission control would send us the Form 24 for the next day on
the teleprinter. If there was time, we had tea and a small treat-cookies or
candy-before the last comm pass of the day, which usually occurred between 10
and 11 at night. Then we said good night to one another and went to our separate
sleeping areas. I floated into Spektr, unrolled my sleeping bag and tethered
it to a handrail. I usually spent some time reading and typing letters to home
on my computer (we used a ham radio packet system to send the messages to the
ground controllers, who sent them to my family by email). At midnight I turned
out the light and floated into my sleeping bag. I always slept soundly until
the alarm went off the next morning.

Quail Eggs and Dwarf Wheat

Our routine on Mir rarely changed, but the days were not monotonous. I was
living every scientist's dream. I had my own lab and worked independently for
much of the day. Before one experiment became dull, it was time to start another,
with new equipment and in a new scientific field. I discussed my work at least
once a day with Bill Gerstenmaier, the NASA flight director, or Gaylen Johnson, the NASA flight surgeon, both at Russian mission control. They coordinated my
activities with the principal investigators-the American and Canadian scientists
who had proposed and designed the experiments. Many times when we started a
new experiment, Gerstenmaier arranged for the principal investigators to be
listening to our radio conversations, so they would be ready to answer any questions
I might have. And this was in the middle of the night back in the U.S.!

My role in each experiment was to do the onboard procedures. Then the data
and samples were returned to the earth on the space shuttle and sent to the
principal investigators for analysis and publication. I believe my experience
on Mir clearly shows the value of performing research on manned space stations.
During some of the experiments, I was able to observe subtle phenomena that
a video or still camera would miss. Because I was familiar with the science
in each experiment, I could sometimes examine the results on the spot and modify
the procedures as needed. Also, if there was a malfunction in the scientific
equipment, I or one of my crewmates could usually fix it. Only one of the 28
experiments scheduled for my mission failed to yield results because of a breakdown
in the equipment.

I started my work on Mir with a biology experiment examining the development
of embryos in fertilized Japanese quail eggs. The eggs were brought to Mir on
the same shuttle flight that I took, then transferred to an incubator on the
space station. Over the next 16 days I removed the 30 eggs one by one from the
incubator and placed them in a 4 percent paraformaldehyde solution to fix the
developing embryos for later analysis. Then I stored the samples at ambient
temperature.

This description makes it sound like a simple experiment, but it required
creative engineering to accomplish the procedure in a microgravity environment.
NASA and Russian safety rules called for three layers of containment for the
fixative solution; if a drop escaped, it could float into a crew member's eye
and cause severe burns. Engineers at the NASA Ames Research Center designed
a system of interlocking clear bags for inserting the eggs into the fixative
and cracking them open. In addition, the entire experiment was enclosed in a
larger bag with gloves attached to its surface, which allowed me to reach inside
the bag without opening it.

Investigators at Ames and several universities analyzed the quail embryos
at the end of my mission to see if they differed from embryos that had developed
in an incubator on the ground. Remarkably, the abnormality rate among the Mir
embryos was 13 percent-more than four times higher than the rate for the control
embryos. The investigators believe two factors may have increased the abnormality
rate: the slightly higher temperature in the Mir incubator and the much higher
radiation levels on the space station. Other experiments determined that the
average radiation exposure on Mir is the equivalent of getting eight chest x-rays
a day. NASA scientists believe, however, that an astronaut would have to spend
at least several years in orbit to raise appreciably his or her risk of developing
cancer.

I was also involved in a long-running experiment to grow wheat in a greenhouse
on the Kristall module. American and Russian scientists wanted to learn how
wheat seeds would grow and mature in a microgravity environment. The experiment
had an important potential application: growing plants could provide oxygen
and food for long-term spaceflight. Scientists focused on the dwarf variety
of wheat because of its short growing season. I planted the seeds in a bed of
zeolite, an absorbent granular material. A computer program controlled the amount
of light and moisture the plants received. Every day we photographed the wheat
stalks and monitored their growth.

At selected times, we harvested a few plants and preserved them in a fixative
solution for later analysis on the ground. One evening, after the plants had
been growing for about 40 days, I noticed seed heads on the tips of the stalks.
I shouted excitedly to my crewmates, who floated by to take a look. John Blaha, the American astronaut who succeeded me on Mir, harvested the mature plants
a few months later and brought more than 300 seed heads back to the earth. But
scientists at Utah State University discovered that all the seed heads were
empty. The investigators speculate that low levels of ethylene in the space
station's atmosphere may have interfered with the pollination of the wheat.
In subsequent research on Mir, astronaut Michael Foale planted a variety of
rapeseed that successfully pollinated.

The microgravity environment on the space station also provided an excellent
platform for experiments in fluid physics and materials science. Scientists
sought to further improve the environment by minimizing vibrations. Mir vibrates
slightly as it orbits the earth, and although the shaking is imperceptible to
humans, it can have an effect on sensitive experiments. The movements of the
crew and airflows on the station can also cause vibrations. To protect experiments
from these disturbances, we placed them on the Microgravity Isolation Mount,
a device built by the Canadian Space Agency. The top half of the isolation mount
floats free, held in place solely by electromagnetic fields.

After running an extensive check of the mount, I used it to isolate a metallurgical
experiment. I placed metal samples in a specially designed furnace, which heated
them to a molten state. Different liquid metals were allowed to diffuse in small
tubes, then slowly cooled. The principal investigators wanted to determine how
molten metals would diffuse without the influence of convection. (In a microgravity
environment, warmer liquids and gases do not rise, and colder ones do not sink.)
After analyzing the results, they learned that the diffusion rate is much slower
than on the earth. During the procedure, one of the brackets in the furnace
was bent out of alignment, threatening the completion of the experiment. But
flight engineer Usachev simply removed the bracket, put it on a workbench and
pounded it straight with a hammer. Needless to say, this kind of repair would
have been impossible if the experiment had taken place on an unmanned spacecraft.

Many of the experiments provided useful data for the engineers designing the
International Space Station. The results from our investigations in fluid physics
are helping the space station's planners build better ventilation and life-support
systems. And our research on how flames propagate in microgravity may lead to
improved procedures for fighting fires on the station.

Safety in Space

Throughout my mission I also performed a series of earth observations. Many
scientists had asked NASA to photograph parts of the planet under varying seasonal
and lighting conditions. Oceanographers, geologists and climatologists would
incorporate the photographs into their research. I usually took the pictures
from the Kvant-2 observation window with a handheld Hasselblad camera. I discovered
that during a long spaceflight, as opposed to a quick space shuttle jaunt, I
could see the flow of seasons across the face of the globe. When I arrived on
Mir at the end of March, the higher latitudes of the Northern Hemisphere were
covered with ice and snow. Within a few weeks, though, I could see huge cracks
in the lakes as the ice started to break up. Seemingly overnight, the Northern
Hemisphere glowed green with spring.

We also documented some unusual events on the earth's surface. One day as
we passed over Mongolia we saw giant plumes of smoke, as though the entire country
were on fire. The amount of smoke so amazed us that we told the ground controllers
about it. Days later they informed us that news of huge forest fires was just
starting to filter out of Mongolia.

For long-duration manned spaceflight, the most important consideration is
not the technology of the spacecraft but the composition of the crew. The main
reason for the success of our Mir mission was the fact that Commander Onufriyenko,
flight engineer Usachev and I were so compatible. It would have been very easy
for language, gender or culture to divide us, but this did not happen. My Russian
crewmates always made sure that I was included in their conversations. Whenever
practical, we worked on projects together. We did not spend time criticizing
one another-if a mistake was made, it was understood, corrected and then forgotten.
Most important, we laughed together a lot.

The competence of my crewmates was one of the reasons I always felt safe on
Mir. When I began my mission, the space station had been in orbit for 10 years,
twice as long as it had been designed to operate. Onufriyenko and Usachev had
to spend most of their time maintaining the station, replacing parts as they
failed and monitoring the systems critical to life support. I soon discovered
that my crewmates could fix just about anything. Many spare parts are stored
on Mir, and more are brought up as needed on the Progress spacecraft. Unlike
the space shuttle, Mir cannot return to the earth for repairs, so the rotating
crews of cosmonauts are trained to keep the station functioning.

Furthermore, the crews on Mir have ample time to respond to most malfunctions.
A hardware failure on the space shuttle demands immediate attention because
the shuttle is the crew's only way to return to the earth. If a piece of vital
equipment breaks down, the astronauts have to repair the damage quickly or end
the mission early, which has happened on a few occasions. But Mir has a lifeboat:
at least one Soyuz spacecraft is always attached to the space station. If a
hardware failure occurs on Mir, it does not threaten the crew's safe return
home. As long as the space station remains habitable, the crew members can analyze
what happened, talk to mission control and then correct the malfunction or work
around the problem.

Only two situations would force the Mir crew to take immediate action: a fire
inside the space station or a rapid depressurization. Both events occurred on
Mir in 1997, after I left the station. In each case, the crew members were able
to contain the damage quickly.

My mission on the space station was supposed to end in August 1996, but my
ride home-shuttle mission STS-79-was delayed for six weeks while NASA engineers
studied abnormal burn patterns on the solid-fuel boosters from a previous shuttle
flight. When I heard about the delay, my first thought was, "Oh, no, not another
month and a half of treadmill running!" Because of the delay, I was still on
Mir when a new Russian crew arrived on the Soyuz spacecraft to relieve Onufriyenko
and Usachev. By the time I finally came back on the shuttle Atlantis on September
26, 1996, I had logged 188 days in space-an American record that still stands.

This June, astronaut Andrew Thomas-the last of the seven NASA astronauts who
have lived on Mir over the past three years-is scheduled to return to the earth,
ending the Shuttle-Mir program. Based on my own experience, I believe there
are several lessons that should be applied to the operation of the International
Space Station. First, the station crew must be chosen carefully. Even if the
space station has the latest in futuristic technology, if the crew members do
not enjoy working together, the flight will be a miserable experience. Second,
NASA must recognize that a long-duration flight is as different from a shuttle
flight as a marathon is from a 100-yard dash. On a typical two-week shuttle
flight, NASA ground controllers assign every moment of the crew's time to some
task. But the crew on a long-duration flight must be treated more like scientists
in a laboratory on the earth. They must have some control over their daily schedules.

Similarly, when a crew trains for a science mission on the space shuttle, the
members practice every procedure until it can be done without even having to
think about it. Training for a mission on the International Space Station needs
to be different. When a crew member starts a new experiment on a long-duration
flight, it might be up to six months after he or she trained for the procedure.
The astronaut will need to spend some time reviewing the experiment. Therefore,
their training should be skill-based. Crew members should learn the skills they
will need during their missions rather than practice every specific procedure.
Also, crew members on a long-duration flight need to be active partners in the
scientific investigations they perform. Experiments should be designed such
that the astronaut knows the science involved and can make judgment calls on
how to proceed. An intellectually engaged crew member is a happy crew member.

When I reflect on my six months on Mir, I have no shortage of memories. But
there is one that captures the legacy of the Shuttle-Mir program. One evening
Onufriyenko, Usachev and I were floating around the table after supper. We were
drinking tea, eating cookies and talking. The cosmonauts were very curious about
my childhood in Texas and Oklahoma. Onufriyenko talked about the Ukrainian village
where he grew up, and Usachev reminisced about his own Russian village. After
a while we realized we had all grown up with the same fear: an atomic war between
our two countries.

I had spent my grade school years living in terror of the Soviet Union. We
practiced bomb drills in our classes, all of us crouching under our desks, never
questioning why. Similarly, Onufriyenko and Usachev had grown up with the knowledge
that U.S. bombers or missiles might zero in on their villages. After talking
about our childhoods some more, we marveled at what an unlikely scenario had
unfolded. Here we were, from countries that were sworn enemies a few years earlier,
living together on a space station in harmony and peace. And, incidentally,
having a great time.

About the author: Shannon W. Lucid is an astronaut at the National Aeronautics
and Space Administration Johnson Space Center in Houston, Tex. She has participated in five spaceflights, including her mission on Mir, logging a total of 223 days
in orbit. She is currently the astronaut representative to the Shuttle-Mir program.
She is still an active-duty astronaut and hopes to be assigned to another NASA
spaceflight.